Neurokinin-1 receptor

Fosaprepitant (MK-0517, L-758,298) is a phosphoryl prodrug for aprepitant. A corticosteroid and a 5-HT 3 receptor antagonist are approved as combination therapies with the selective substance P (NK-1 receptor) antagonist aprepitant to prevent acute and delayed chemotherapy-induced nausea and vomiting. [1]

Fosaprepitant is intravenously administered and within 30 minutes, transforms into an aprepitant due to the action of ubiquitous phosphatases. Fosaprepitant has a well-tolerated maximum dosage of 150 mg (1 mg/ml), and its AUC for Fosaprepitant 115 mg and Aprecipitant 125 mg are bioequivalent. On day 1 of a 3-day oral aprepitant regimen, fosaprepitant 115 mg has been submitted for FDA approval as an alternative. On days 2 and 3, oral aprepitant is administered. [1]

Sprague-Dawley rats were injected with morphine (10 mg/kg twice daily) and/or fosaprepitant (30 mg/kg once daily) for 7 days. Pain threshold was assessed by the hot plate test. Expression of SP and calcitonin gene-related peptide (CGRP) in the spinal cords of these rats was evaluated by immunohistochemistry.[2]

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Fosaprepitant (also known as MK-0517 and L-758,298) is a water-soluble phosphoryl prodrug for aprepitant, which, when administered intravenously, is converted to aprepitant within 30 min of intravenous administration via the action of ubiquitous phosphatases. Owing to the rapid conversion of fosaprepitant to the active form (aprepitant), fosaprepitant 115 mg provided the same aprepitant exposure in terms of AUC as aprepitant 12 mg orally, and fosaprepitant is expected to provide a correspondingly similar antiemetic effect as aprepitant. Clinical studies have suggested that fosaprepitant could be appropriate as an intravenous alternative to the aprepitant oral capsule. In a study in healthy subjects, fosaprepitant 115 mg was generally well tolerated at a final drug concentration of 1 mg/ml, and fosaprepitant 115 mg was AUC bioequivalent to aprepitant 125 mg. Fosaprepitant in the dose of 115 mg has been approved by the US FDA, the EU and the Australian authorities on day 1 of a 3-day oral aprepitant regimen, with oral aprepitant administered on days 2 and 3. Fosaprepitant may be a useful parenteral alternative to oral aprepitant. Further study is needed to clarify the utility of fosaprepitant in the prevention of CINV and to clarify optimal dosing regimens that may be appropriate substitutes for oral aprepitant[2].

[1]. Expert Opin Investig Drugs. 2007 Dec;16(12):1977-85.

[2]. Role of fosaprepitant, a neurokinin Type 1 receptor antagonist, in morphine-induced antinociception in rats. Indian J Pharmacol. 2016 Jul-Aug; 48(4): 394-398.
[3]. Fosaprepitant: a neurokinin-1 receptor antagonist for the prevention of chemotherapy-induced nausea and vomiting. Expert Rev Anticancer Ther . 2008 Nov;8(11):1733-42.

Fosaprepitant dimeglumine is an organoammonium salt obtained by reaction of fosaprepitant with two equivalents of 1-deoxy-1-(methylamino)-D-glucitol. A substance P/neurokinin 1 (NK1) receptor antagonist. Aprepitant is a selective high-affinity antagonist of human substance P/neurokinin 1 (NK1) receptors. Aprepitant has little or no affinity for serotonin (5-HT3), dopamine, and corticosteroid receptors, the targets of existing therapies for chemotherapy-induced nausea and vomiting and postoperative nausea and vomiting It has a role as a prodrug, an antiemetic and a neurokinin-1 receptor antagonist. It contains a fosaprepitant(2-). ChEBI

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Fosaprepitant Dimeglumine is the dimeglumine salt form of fosaprepitant, the water-soluble, N-phosphorylated prodrug of aprepitant, with antiemetic activity. Upon intravenous administration and rapid conversion to aprepitant, this agent binds selectively to the human substance P/neurokinin 1 (NK1) receptors in the central nervous system (CNS). This inhibits receptor binding of the endogenous substance P and prevents substance P-induced emesis.
Prevention of nausea and vomiting associated with highly and moderately emetogenic cancer chemotherapy in adults and paediatric patients aged 6 months and older. Ivemend 150 mg is given as part of a combination therapy.

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Purpose: Fosaprepitant dimeglumine for injection is the water-soluble phosphorylated prodrug of the neurokinin-1 receptor antagonist aprepitant. Both agents are approved (in combination with a 5-HT3 antagonist and a corticosteroid) for prevention of chemotherapy-induced nausea and vomiting. Because fosaprepitant is likely to be combined and stored in the same intravenous (IV) bag with 5-HT3 antagonists and corticosteroids, the in vitro compatibility of fosaprepitant with these agents and other IV diluents was assessed.[3]
Methods: Fosaprepitant (1 mg/mL in 0.9 % sodium chloride injection solution) was combined in binary or tertiary fashion with therapeutic-dose preparations of a 5-HT3 antagonist (ondansetron, granisetron, palonosetron, or tropisetron) and/or a corticosteroid (dexamethasone sodium phosphate or methylprednisolone sodium succinate). For diluent compatibility assessment, fosaprepitant was also prepared 1 mg/mL in 0.9 % sodium chloride injection solution, water for injection, or 5 % dextrose injection solution. After 24-h storage under ambient conditions, samples were assayed for degradation.[3]
Results: Fosaprepitant demonstrated compatibility when combined in the same IV infusion bag with common 5-HT3 antagonists and corticosteroids for storage and IV coadministration, with the exception of palonosetron (incompatible under all experimental conditions) and tropisetron (incompatible unless combined with a corticosteroid). No incompatibility was observed between fosaprepitant and any of the 3 diluents tested.[3]
Conclusions: Use of fosaprepitant in combination with other antiemetics may provide a flexible option for administration of antiemetics to patients receiving moderately or highly emetogenic chemotherapy.[3]

C37H56F7N6O16P

1004.8337

1004.34

C, 44.23; H, 5.62; F, 13.23; N, 8.36; O, 25.48; P, 3.08

265121-04-8

Fosaprepitant; 172673-20-0; Fosaprepitant-d4 dimeglumine

135564864

White solid powder

366.08

C[C@H](C1=CC(=CC(=C1)C(F)(F)F)C(F)(F)F)O[C@@H]2[C@@H](N(CCO2)CC3=NN(C(=O)N3)P(=O)(O)O)C4=CC=C(C=C4)F.CNC[C@@H]([C@H]([C@@H]([C@@H](CO)O)O)O)O.CNC[C@@H]([C@H]([C@@H]([C@@H](CO)O)O)O)O

VRQHBYGYXDWZDL-OOZCZQCLSA-N

InChI=1S/C23H22F7N4O6P.2C7H17NO5/c1-12(14-8-15(22(25,26)27)10-16(9-14)23(28,29)30)40-20-19(13-2-4-17(24)5-3-13)33(6-7-39-20)11-18-31-21(35)34(32-18)41(36,37)38;2*1-8-2-4(10)6(12)7(13)5(11)3-9/h2-5,8-10,12,19-20H,6-7,11H2,1H3,(H,31,32,35)(H2,36,37,38);2*4-13H,2-3H2,1H3/t12-,19+,20-;2*4-,5+,6+,7+/m100/s1

[3-[[(2R,3S)-2-[(1R)-1-[3,5-bis(trifluoromethyl)phenyl]ethoxy]-3-(4-fluorophenyl)morpholin-4-yl]methyl]-5-oxo-4H-1,2,4-triazol-1-yl]phosphonic acid;(2R,3R,4R,5S)-6-(methylamino)hexane-1,2,3,4,5-pentol

MK0517; MK 0517; MK-0517; Fosaprepitant dimeglumine; Fosaprepitant dimeglumine salt; Ivemend; Fosaprepitant meglumine; MK-0517; Fosaprepitant (dimeglumine); UNII-D35FM8T64X; Emend; Inemend

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: (1). This product is not stable in solution, please use freshly prepared working solution for optimal results.  (2). Please store this product in a sealed and protected environment, avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

H2O: ~50 mg/mL (~49.8 mM)

Solubility in Formulation 1: 100 mg/mL (99.52 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication.

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 (Please use freshly prepared in vivo formulations for optimal results.)